Manure refinement affects apple rhizosphere bacterial community structure: a study in sandy soil

Area of Science:

• Agricultural Science
• Soil Microbiology
• Environmental Science

Background:

• Manure application is a common practice in agriculture to improve soil fertility.
• Understanding the impact of varying manure ratios on soil bacterial communities and enzyme activities is crucial for sustainable orchard management.

Purpose of the Study:

• To investigate the effects of different manure application ratios on the bacterial community structure and soil enzyme activities in an apple orchard.
• To determine the optimal manure ratio for enhancing soil quality and microbial health.

Main Methods:

• DNA-based pyrosequencing was employed to analyze bacterial community structure in sandy soil samples from apple orchards with five different manure percentages (5% to 25%).
• Redundancy analysis and clustering were used to correlate bacterial classes with manure ratios and group soil samples.
• Soil enzyme activities (urease and saccharase) and organic matter content were measured.

Main Results:

• Bacterial communities were dominated by Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria, and Bacteroidetes, with Proteobacteria decreasing as manure ratio increased.
• Soil samples clustered into low, medium, and high manure groups, with differences primarily in bacterial quantity rather than species variety.
• Medium manure levels (10-15%) resulted in the highest urease and saccharase activity, and 5-20% manure improved bacterial diversity compared to control and 25% treatments.

Conclusions:

• The application of a proper manure ratio significantly influences soil enzyme activity and bacterial community patterns in apple orchards.
• Excessive manure application can have detrimental effects on soil quality, highlighting the importance of balanced fertilization for sustainable agriculture.